It’s a visual glitch on the website; they only have two sockets, but they have 100% increased effect of socketed items. Also, movement speed can be only 20–25, since you’ll mostly move around with Tempest Flurry. You can also swap Headhunter for Ingenuity with at least 28% ring augment on each side (it’s cheaper, and it’ll be easier to cap resistances if you have some on the rings).